frank, originally named takashi, is a young sesame kishu and was a young student of the iga clan. he and tegan were close like brother and sister. tegan secretly told him of her and simon's relationship and of her pregnancy, which he approved. after akame confronted tegan and she leaves, takashi confronts akame and accidentally reveals that she's pregnant with simon's sons. angered that takashi kept a secret from him, akame exiles takashi. takashi leaves and goes to look for tegan and simon throughout japan and then south korea and china, but couldn't find them.
it was when he returned to japan that he meets a syndicate named the Tarantula Yakuza, lead by a woman named Tara.
they reveal to takashi that tegan and simon are dead, and lied to him that akame killed them on their island home. fueled with rage, takashi joins the syndicate and changes his name to his new codename, frank. he soon has a new weapon with him, an augmented jintachi. he was instructed to bring back a human named dorei.
however, once he suceeds his mission, tara reveals her true colours and orders takashi's execution. she then tells takashi the truth of tegan and simon's deaths: simon was killed by cutler who was mutatated and tegan was murdered by nicholai. horrified that he was used, takashi was dragged away to be excuted. however he was quickly rescued by akame, izou and shirozaru. akame tells takashi that he was sorry for not saving tegan but now he saved takashi. takashi accepts the apology and joins the ohu army in the fight against tara and Tarantula Yakuza.